what am i doing wrong? please help!!! (algebra)?

Question

ive done these problems like 6 times and keep getting the same answers but they don't work when i check them. please help me...

7y - 2(y - 4) = 8y - (4y + 13)

= 7y - 2y + 8 = 8y - 4y -13
= 5y + 8 = 4y - 13
= 5y - 4y = -13 - 8
= y = -21

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-6 + 10y + 18 = 4(2y - 6) - 8

= 10y + 12 = 8y -24 -8
= 10y + 12 = 8y - 32
= 10y - 8y = -32 - 12
= 2y = -44
= y = -22


(But when I go to check them, the variables dont work please help me and tell me what i am doing wrong)

then why when i plug in the varibles the sides are unequal? ugh my brain hurts

LOL how embarassing.

Thanks

LOL how embarassing.

Thanks

Answer 1

It looks like you're checking them incorrectly!

7(-21) - 2(-25) = 8(-21) - (4(-21) + 13)
<=> -147 + 50 = -168 - (-84 + 13)
<=> -97 = -168 - (-71)
<=> -97 = -97

-6 + 10(-22) + 18 = 4(2(-22) - 6) - 8
<=> -6 - 220 + 18 = 4(-44 - 6) - 8
<=> -208 = 4(-50) - 8
<=> -208 = -200 - 8
<=> -208 = -208.

Answer 2

Your answer is correct for both.

7y - 2(y - 4) = 8y - (4y + 13)
=> 7(-21) - 2((-21) - 4) = 8(-21) - (4(-21) + 13)
=> -147 - 2(-25) = -168 - (-84 + 13)
=> -147 +50 = -168 - (-71)
=> -97 = -168 + 71
=> -97 = -97

-6 + 10y + 18 = 4(2y - 6) - 8
=> -6 + 10(-22) + 18 = 4(2(-22) - 6) - 8
=> (-220) + 12 = 4((-44) - 6) - 8
=> -208 = 4(-50) - 8
=> -208 = -200 - 8
=> -208 = -208

Answer 3

Your answers are absolutely correct

Answer 4

no, you ARE correct for both of them... i think you must be checking your answers wrongly?